In-home TB Testing Using GeneXpert Edge is Acceptable, Feasible, and Improves the Proportion of Symptomatic Household Contacts Tested for TB: A Proof-of-Concept Study

Abstract

Background Household contact investigations (HCI) are effective for finding tuberculosis (TB) cases but hindered by low referral uptake for clinic-based evaluation and testing. We assessed the acceptability and feasibility of in-home testing of household contacts (HHC) using the GeneXpert Edge platform. Methods We conducted a two-arm, randomized study in Eastern Cape, South Africa. HHCs were verbally assessed using the WHO-recommended four-symptom screen. Households with ≥1 eligible symptomatic contact were randomized. Intervention households received in-home GeneXpert MTB/RIF molecular testing. GeneXpert-positive HHCs were referred for clinic-based treatment. Standard-of-care households were referred for clinic-based sputum collection and testing. We defined acceptability as agreeing to in-home testing and feasibility as generation of valid Xpert MTB/RIF results. The proportion and timeliness of test results received was compared between groups. Results Eighty-four households were randomized (n=42 per arm). Of 100 eligible HHCs identified, 98/100 (98%) provided consent. Of 51 HHCs allocated to the intervention arm, all accepted in-home testing; of those, 24/51 (47%) were sputum productive and 23/24 (96%) received their test results. Of 47 HCCs allocated to standard-of-care, 7 (15%) presented for clinic-based TB evaluation, 6/47 (13%) were tested and 4/6 (67%) returned for their results. The median (IQR) number of days from screening to receiving-of-test-results was 0 (0) and 16.5 (11-15) in intervention and standard-of-care arms, respectively. Conclusions In-home testing for TB was acceptable, feasible and increased HHCs with a molecular test result. In-home testing mitigates a major limitation of HCIs (dependency on clinic-based referral), revealing new strategies for enhancing early case detection.